Convert __sigsetjmp code to allow building as Thumb.
ports/ChangeLog.arm:
2013-10-04 Will Newton <will.newton@linaro.org>
* sysdeps/arm/setjmp.S (NO_THUMB): Remove define.
(__sigsetjmp): Use Thumb supported instructions.
Convert __longjmp code to allow building as Thumb.
ports/ChangeLog.arm:
2013-10-04 Will Newton <will.newton@linaro.org>
* sysdeps/arm/__longjmp.S (NO_THUMB): Remove define.
(__longjmp): Use Thumb supported instructions.
* sysdeps/unix/sysv/linux/arm/____longjmp_chk.S (NO_THUMB):
Remove define.
Add some comments and call free on all potentially allocated pointers.
Also remove duplicate check for NULL pointer.
ChangeLog:
2013-10-04 Will Newton <will.newton@linaro.org>
* malloc/tst-valloc.c: Add comments.
(do_test): Add comments and call free on all potentially
allocated pointers. Remove duplicate check for NULL pointer.
Add space after cast.
Add some comments and call free on all potentially allocated pointers.
Also remove duplicate check for NULL pointer.
ChangeLog:
2013-10-04 Will Newton <will.newton@linaro.org>
* malloc/tst-pvalloc.c: Add comments.
(do_test): Add comments and call free on all potentially
allocated pointers. Remove duplicate check for NULL pointer.
Add space after cast.
Add some comments and call free on all potentially allocated pointers.
ChangeLog:
2013-10-04 Will Newton <will.newton@linaro.org>
* malloc/tst-posix_memalign.c: Add comments.
(do_test): Add comments and call free on all potentially
allocated pointers. Add space after cast.
* sysdeps/powerpc/powerpc32/dl-machine.c (__process_machine_rela):
Use stdint types in rather than __attribute__((mode())).
* sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela): Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00096.html
This adds the basic configury bits for powerpc64le and powerpcle.
* configure.in: Map powerpc64le and powerpcle to base_machine/machine.
* configure: Regenerate.
* nptl/shlib-versions: Powerpc*le starts at 2.18.
* shlib-versions: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00095.html
I found this useful at one stage when I was seeing a huge number of
memrchr failures all of test number 10.
* string/tester.c (test_memrchr): Increment reported test cycle.
http://sourceware.org/ml/libc-alpha/2013-08/msg00094.html
Using plain %s here runs the risk of segfaulting when displaying the
string. src and dst aren't zero terminated strings.
* string/test-memcpy.c (do_one_test): When reporting errors, print
string address and don't overrun end of string.
http://sourceware.org/ml/libc-alpha/2013-08/msg00105.html
Like strnlen, memchr and memrchr had a number of defects fixed by this
patch as well as adding little-endian support. The first one I
noticed was that the entry to the main loop needlessly checked for
"are we done yet?" when we know the size is large enough that we can't
be done. The second defect I noticed was that the main loop count was
wrong, which in turn meant that the small loop needed to handle an
extra word. Thirdly, there is nothing to say that the string can't
wrap around zero, except of course that we'd normally hit a segfault
on trying to read from address zero. Fixing that simplified a number
of places:
- /* Are we done already? */
- addi r9,r8,8
- cmpld r9,r7
- bge L(null)
becomes
+ cmpld r8,r7
+ beqlr
However, the exit gets an extra test because I test for being on the
last word then if so whether the byte offset is less than the end.
Overall, the change is a win.
Lastly, memrchr used the wrong cache hint.
* sysdeps/powerpc/powerpc64/power7/memchr.S: Replace rlwimi with
insrdi. Make better use of reg selection to speed exit slightly.
Schedule entry path a little better. Remove useless "are we done"
checks on entry to main loop. Handle wrapping around zero address.
Correct main loop count. Handle single left-over word from main
loop inline rather than by using loop_small. Remove extra word
case in loop_small caused by wrong loop count. Add little-endian
support.
* sysdeps/powerpc/powerpc32/power7/memchr.S: Likewise.
* sysdeps/powerpc/powerpc64/power7/memrchr.S: Likewise. Use proper
cache hint.
* sysdeps/powerpc/powerpc32/power7/memrchr.S: Likewise.
* sysdeps/powerpc/powerpc64/power7/rawmemchr.S: Add little-endian
support. Avoid rlwimi.
* sysdeps/powerpc/powerpc32/power7/rawmemchr.S: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00104.html
One of the things I noticed when looking at power7 timing is that rlwimi
is cracked and the two resulting insns have a register dependency.
That makes it a little slower than the equivalent rldimi.
* sysdeps/powerpc/powerpc64/memset.S: Replace rlwimi with
insrdi. Formatting.
* sysdeps/powerpc/powerpc64/power4/memset.S: Likewise.
* sysdeps/powerpc/powerpc64/power6/memset.S: Likewise.
* sysdeps/powerpc/powerpc64/power7/memset.S: Likewise.
* sysdeps/powerpc/powerpc32/power4/memset.S: Likewise.
* sysdeps/powerpc/powerpc32/power6/memset.S: Likewise.
* sysdeps/powerpc/powerpc32/power7/memset.S: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00103.html
LIttle-endian support for memcpy. I spent some time cleaning up the
64-bit power7 memcpy, in order to avoid the extra alignment traps
power7 takes for little-endian. It probably would have been better
to copy the linux kernel version of memcpy.
* sysdeps/powerpc/powerpc32/power4/memcpy.S: Add little endian support.
* sysdeps/powerpc/powerpc32/power6/memcpy.S: Likewise.
* sysdeps/powerpc/powerpc32/power7/memcpy.S: Likewise.
* sysdeps/powerpc/powerpc32/power7/mempcpy.S: Likewise.
* sysdeps/powerpc/powerpc64/memcpy.S: Likewise.
* sysdeps/powerpc/powerpc64/power4/memcpy.S: Likewise.
* sysdeps/powerpc/powerpc64/power6/memcpy.S: Likewise.
* sysdeps/powerpc/powerpc64/power7/memcpy.S: Likewise.
* sysdeps/powerpc/powerpc64/power7/mempcpy.S: Likewise. Make better
use of regs. Use power7 mtocrf. Tidy function tails.
http://sourceware.org/ml/libc-alpha/2013-08/msg00102.html
This is a rather large patch due to formatting and renaming. The
formatting changes were to make it possible to compare power7 and
power4 versions of memcmp. Using different register defines came
about while I was wrestling with the code, trying to find spare
registers at one stage. I found it much simpler if we refer to a reg
by the same name throughout a function, so it's better if short-term
multiple use regs like rTMP are referred to using their register
number. I made the cr field usage changes when attempting to reload
rWORDn regs in the exit path to byte swap before comparing when
little-endian. That proved a bad idea due to the pipelining involved
in the main loop; Offsets to reload the regs were different first
time around the loop.. Anyway, I left the cr field usage changes in
place for consistency.
Aside from these more-or-less cosmetic changes, I fixed a number of
places where an early exit path restores regs unnecessarily, removed
some dead code, and optimised one or two exits.
* sysdeps/powerpc/powerpc64/power7/memcmp.S: Add little-endian support.
Formatting. Consistently use rXXX register defines or rN defines.
Use early exit labels that avoid restoring unused non-volatile regs.
Make cr field use more consistent with rWORDn compares. Rename
regs used as shift registers for unaligned loop, using rN defines
for short lifetime/multiple use regs.
* sysdeps/powerpc/powerpc64/power4/memcmp.S: Likewise.
* sysdeps/powerpc/powerpc32/power7/memcmp.S: Likewise. Exit with
addi 1,1,64 to pop stack frame. Simplify return value code.
* sysdeps/powerpc/powerpc32/power4/memcmp.S: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00101.html
Adds little-endian support to optimised strchr assembly. I've also
tweaked the big-endian code a little. In power7/strchr.S there's a
check in the tail of the function that we didn't match 0 before
finding a c match, done by comparing leading zero counts. It's just
as valid, and quicker, to compare the raw output from cmpb.
Another little tweak is to use rldimi/insrdi in place of rlwimi for
the power7 strchr functions. Since rlwimi is cracked, it is a few
cycles slower. rldimi can be used on the 32-bit power7 functions
too.
* sysdeps/powerpc/powerpc64/power7/strchr.S (strchr): Add little-endian
support. Correct typos, formatting. Optimize tail. Use insrdi
rather than rlwimi.
* sysdeps/powerpc/powerpc32/power7/strchr.S: Likewise.
* sysdeps/powerpc/powerpc64/power7/strchrnul.S (__strchrnul): Add
little-endian support. Correct typos.
* sysdeps/powerpc/powerpc32/power7/strchrnul.S: Likewise. Use insrdi
rather than rlwimi.
* sysdeps/powerpc/powerpc64/strchr.S (rTMP4, rTMP5): Define. Use
in loop and entry code to keep "and." results.
(strchr): Add little-endian support. Comment. Move cntlzd
earlier in tail.
* sysdeps/powerpc/powerpc32/strchr.S: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00100.html
The strcpy changes for little-endian are quite straight-forward, just
a matter of rotating the last word differently.
I'll note that the powerpc64 version of stpcpy is just begging to be
converted to use 64-bit loads and stores..
* sysdeps/powerpc/powerpc64/strcpy.S: Add little-endian support:
* sysdeps/powerpc/powerpc32/strcpy.S: Likewise.
* sysdeps/powerpc/powerpc64/stpcpy.S: Likewise.
* sysdeps/powerpc/powerpc32/stpcpy.S: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00099.html
More little-endian support. I leave the main strcmp loops unchanged,
(well, except for renumbering rTMP to something other than r0 since
it's needed in an addi insn) and modify the tail for little-endian.
I noticed some of the big-endian tail code was a little untidy so have
cleaned that up too.
* sysdeps/powerpc/powerpc64/strcmp.S (rTMP2): Define as r0.
(rTMP): Define as r11.
(strcmp): Add little-endian support. Optimise tail.
* sysdeps/powerpc/powerpc32/strcmp.S: Similarly.
* sysdeps/powerpc/powerpc64/strncmp.S: Likewise.
* sysdeps/powerpc/powerpc32/strncmp.S: Likewise.
* sysdeps/powerpc/powerpc64/power4/strncmp.S: Likewise.
* sysdeps/powerpc/powerpc32/power4/strncmp.S: Likewise.
* sysdeps/powerpc/powerpc64/power7/strncmp.S: Likewise.
* sysdeps/powerpc/powerpc32/power7/strncmp.S: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00098.html
The existing strnlen code has a number of defects, so this patch is more
than just adding little-endian support. The changes here are similar to
those for memchr.
* sysdeps/powerpc/powerpc64/power7/strnlen.S (strnlen): Add
little-endian support. Remove unnecessary "are we done" tests.
Handle "s" wrapping around zero and extremely large "size".
Correct main loop count. Handle single left-over word from main
loop inline rather than by using small_loop. Correct comments.
Delete "zero" tail, use "end_max" instead.
* sysdeps/powerpc/powerpc32/power7/strnlen.S: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00097.html
This is the first of nine patches adding little-endian support to the
existing optimised string and memory functions. I did spend some
time with a power7 simulator looking at cycle by cycle behaviour for
memchr, but most of these patches have not been run on cpu simulators
to check that we are going as fast as possible. I'm sure PowerPC can
do better. However, the little-endian support mostly leaves main
loops unchanged, so I'm banking on previous authors having done a
good job on big-endian.. As with most code you stare at long enough,
I found some improvements for big-endian too.
Little-endian support for strlen. Like most of the string functions,
I leave the main word or multiple-word loops substantially unchanged,
just needing to modify the tail.
Removing the branch in the power7 functions is just a tidy. .align
produces a branch anyway. Modifying regs in the non-power7 functions
is to suit the new little-endian tail.
* sysdeps/powerpc/powerpc64/power7/strlen.S (strlen): Add little-endian
support. Don't branch over align.
* sysdeps/powerpc/powerpc32/power7/strlen.S: Likewise.
* sysdeps/powerpc/powerpc64/strlen.S (strlen): Add little-endian support.
Rearrange tmp reg use to suit. Comment.
* sysdeps/powerpc/powerpc32/strlen.S: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00093.html
This copies the sparc version of sigstack.h, which gives powerpc
#define MINSIGSTKSZ 4096
#define SIGSTKSZ 16384
Before the VSX changes, struct rt_sigframe size was 1920 plus 128 for
__SIGNAL_FRAMESIZE giving ppc64 exactly the default MINSIGSTKSZ of
2048.
After VSX, ucontext increased by 256 bytes. Oops, we're over
MINSIGSTKSZ, so powerpc has been using the wrong value for quite a
while. Add another ucontext for TM and rt_sigframe is now at 3872,
giving actual MINSIGSTKSZ of 4000.
The glibc testcase that I was looking at was tst-cancel21, which
allocates 2*SIGSTKSZ (not because the test is trying to be
conservative, but because the test actually has nested signal stack
frames). We blew the allocation by 48 bytes when using current
mainline gcc to compile glibc (le ppc64).
The required stack depth in _dl_lookup_symbol_x from the top of the
next signal frame was 10944 bytes. I guess you'd want to add 288 to
that, implying an actual SIGSTKSZ of 11232.
* sysdeps/unix/sysv/linux/powerpc/bits/sigstack.h: New file.
http://sourceware.org/ml/libc-alpha/2013-08/msg00092.html
Use conditional form of branch and link to avoid destroying the cpu
link stack used to predict blr return addresses.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S: Use
conditional form of branch and link when obtaining pc.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/makecontext.S: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00091.html
More LE support, correcting word accesses to _dl_hwcap.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/getcontext-common.S: Use
HIWORD/LOWORD.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/setcontext-common.S: Ditto.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/swapcontext-common.S: Ditto.
http://sourceware.org/ml/libc-alpha/2013-08/msg00090.html
This patch fixes symbol versioning in setjmp/longjmp. The existing
code uses raw versions, which results in wrong symbol versioning when
you want to build glibc with a base version of 2.19 for LE.
Note that the merging the 64-bit and 32-bit versions in novmx-lonjmp.c
and pt-longjmp.c doesn't result in GLIBC_2.0 versions for 64-bit, due
to the base in shlib_versions.
* sysdeps/powerpc/longjmp.c: Use proper symbol versioning macros.
* sysdeps/powerpc/novmx-longjmp.c: Likewise.
* sysdeps/powerpc/powerpc32/bsd-_setjmp.S: Likewise.
* sysdeps/powerpc/powerpc32/bsd-setjmp.S: Likewise.
* sysdeps/powerpc/powerpc32/fpu/__longjmp.S: Likewise.
* sysdeps/powerpc/powerpc32/fpu/setjmp.S: Likewise.
* sysdeps/powerpc/powerpc32/mcount.c: Likewise.
* sysdeps/powerpc/powerpc32/setjmp.S: Likewise.
* sysdeps/powerpc/powerpc64/setjmp.S: Likewise.
* nptl/sysdeps/unix/sysv/linux/powerpc/pt-longjmp.c: Likewise.
http://sourceware.org/ml/libc-alpha/2013-08/msg00089.html
Little-endian fixes for setjmp/longjmp. When writing these I noticed
the setjmp code corrupts the non volatile VMX registers when using an
unaligned buffer. Anton fixed this, and also simplified it quite a
bit.
The current code uses boilerplate for the case where we want to store
16 bytes to an unaligned address. For that we have to do a
read/modify/write of two aligned 16 byte quantities. In our case we
are storing a bunch of back to back data (consective VMX registers),
and only the start and end of the region need the read/modify/write.
[BZ #15723]
* sysdeps/powerpc/jmpbuf-offsets.h: Comment fix.
* sysdeps/powerpc/powerpc32/fpu/__longjmp-common.S: Correct
_dl_hwcap access for little-endian.
* sysdeps/powerpc/powerpc32/fpu/setjmp-common.S: Likewise. Don't
destroy vmx regs when saving unaligned.
* sysdeps/powerpc/powerpc64/__longjmp-common.S: Correct CR load.
* sysdeps/powerpc/powerpc64/setjmp-common.S: Likewise CR save. Don't
destroy vmx regs when saving unaligned.
http://sourceware.org/ml/libc-alpha/2013-08/msg00088.html
* sysdeps/powerpc/powerpc32/fpu/s_roundf.S: Increase alignment of
constants to usual value for .cst8 section, and remove redundant
high address load.
* sysdeps/powerpc/powerpc32/power4/fpu/s_llround.S: Use float
constant for 0x1p52. Load little-endian words of double from
correct stack offsets.
http://sourceware.org/ml/libc-alpha/2013-07/msg00201.html
These two functions oddly test x+1>0 when a double x is >= 0.0, and
similarly when x is negative. I don't see the point of that since the
test should always be true. I also don't see any need to convert x+1
to integer rather than simply using xr+1. Note that the standard
allows these functions to return any value when the input is outside
the range of long long, but it's not too hard to prevent xr+1
overflowing so that's what I've done.
(With rounding mode FE_UPWARD, x+1 can be a lot more than what you
might naively expect, but perhaps that situation was covered by the
x - xrf < 1.0 test.)
* sysdeps/powerpc/fpu/s_llround.c (__llround): Rewrite.
* sysdeps/powerpc/fpu/s_llroundf.c (__llroundf): Rewrite.
http://sourceware.org/ml/libc-alpha/2013-07/msg00200.html
This works around the fact that vsx is disabled in current
little-endian gcc. Also, float constants take 4 bytes in memory
vs. 16 bytes for vector constants, and we don't need to write one lot
of masks for double (register format) and another for float (mem
format).
* sysdeps/powerpc/fpu/s_float_bitwise.h (__float_and_test28): Don't
use vector int constants.
(__float_and_test24, __float_and8, __float_get_exp): Likewise.
http://sourceware.org/ml/libc-alpha/2013-07/msg00197.html
A rewrite to make this code correct for little-endian.
* sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c (mynumber): Replace
union 32-bit int array member with 64-bit int array.
(t515, tm256): Double rather than long double.
(__ieee754_sqrtl): Rewrite using 64-bit arithmetic.
http://sourceware.org/ml/libc-alpha/2013-08/msg00085.html
Rid ourselves of ieee854.
* sysdeps/ieee754/ldbl-128ibm/ieee754.h (union ieee854_long_double):
Delete.
(IEEE854_LONG_DOUBLE_BIAS): Delete.
* sysdeps/ieee754/ldbl-128ibm/math_ldbl.h: Don't include ieee854
version of math_ldbl.h.
http://sourceware.org/ml/libc-alpha/2013-08/msg00084.html
Another batch of ieee854 macros and union replacement. These four
files also have bugs fixed with this patch. The fact that the two
doubles in an IBM long double may have different signs means that
negation and absolute value operations can't just twiddle one sign bit
as you can with ieee864 style extended double. fmodl, remainderl,
erfl and erfcl all had errors of this type. erfl also returned +1 for
large magnitude negative input where it should return -1. The hypotl
error is innocuous since the value adjusted twice is only used as a
flag. The e_hypotl.c tests for large "a" and small "b" are mutually
exclusive because we've already exited when x/y > 2**120. That allows
some further small simplifications.
[BZ #15734], [BZ #15735]
* sysdeps/ieee754/ldbl-128ibm/e_fmodl.c (__ieee754_fmodl): Rewrite
all uses of ieee875 long double macros and unions. Simplify test
for 0.0L. Correct |x|<|y| and |x|=|y| test. Use
ldbl_extract_mantissa value for ix,iy exponents. Properly
normalize after ldbl_extract_mantissa, and don't add hidden bit
already handled. Don't treat low word of ieee854 mantissa like
low word of IBM long double and mask off bit when testing for
zero.
* sysdeps/ieee754/ldbl-128ibm/e_hypotl.c (__ieee754_hypotl): Rewrite
all uses of ieee875 long double macros and unions. Simplify tests
for 0.0L and inf. Correct double adjustment of k. Delete dead code
adjusting ha,hb. Simplify code setting kld. Delete two600 and
two1022, instead use their values. Recognise that tests for large
"a" and small "b" are mutually exclusive. Rename vars. Comment.
* sysdeps/ieee754/ldbl-128ibm/e_remainderl.c (__ieee754_remainderl):
Rewrite all uses of ieee875 long double macros and unions. Simplify
test for 0.0L and nan. Correct negation.
* sysdeps/ieee754/ldbl-128ibm/s_erfl.c (__erfl): Rewrite all uses of
ieee875 long double macros and unions. Correct output for large
magnitude x. Correct absolute value calculation.
(__erfcl): Likewise.
* math/libm-test.inc: Add tests for errors discovered in IBM long
double versions of fmodl, remainderl, erfl and erfcl.
http://sourceware.org/ml/libc-alpha/2013-08/msg00083.html
Further replacement of ieee854 macros and unions. These files also
have some optimisations for comparison against 0.0L, infinity and nan.
Since the ABI specifies that the high double of an IBM long double
pair is the value rounded to double, a high double of 0.0 means the
low double must also be 0.0. The ABI also says that infinity and
nan are encoded in the high double, with the low double unspecified.
This means that tests for 0.0L, +/-Infinity and +/-NaN need only check
the high double.
* sysdeps/ieee754/ldbl-128ibm/e_atan2l.c (__ieee754_atan2l): Rewrite
all uses of ieee854 long double macros and unions. Simplify tests
for long doubles that are fully specified by the high double.
* sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c (__ieee754_gammal_r):
Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_ilogbl.c (__ieee754_ilogbl): Likewise.
Remove dead code too.
* sysdeps/ieee754/ldbl-128ibm/e_jnl.c (__ieee754_jnl): Likewise.
(__ieee754_ynl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_log10l.c (__ieee754_log10l): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_logl.c (__ieee754_logl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Likewise.
Remove dead code too.
* sysdeps/ieee754/ldbl-128ibm/k_tanl.c (__kernel_tanl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_expm1l.c (__expm1l): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_frexpl.c (__frexpl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_isinf_nsl.c (__isinf_nsl): Likewise.
Simplify.
* sysdeps/ieee754/ldbl-128ibm/s_isinfl.c (___isinfl): Likewise.
Simplify.
* sysdeps/ieee754/ldbl-128ibm/s_log1pl.c (__log1pl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_modfl.c (__modfl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c (__nextafterl): Likewise.
Comment on variable precision.
* sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf):
Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_remquol.c (__remquol): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_scalblnl.c (__scalblnl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_scalbnl.c (__scalbnl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_tanhl.c (__tanhl): Likewise.
* sysdeps/powerpc/fpu/libm-test-ulps: Adjust tan_towardzero ulps.